New Research on Snakebite Envenoming Reveals Promising Small Molecule Therapeutics

New research conducted by Anandie le Roux and colleagues at North-West University in Potchefstroom, South Africa, has identified several small molecule therapeutics (SMTs) that demonstrate the potential to treat snakebite envenoming. According to the study, these SMTs have shown efficacy in preclinical models of snakebite envenoming, with varespladib being granted orphan drug status for its potential to treat snakebite. The research investigated the potential of four SMTs to neutralize toxic components present in the venom of southern African snake species.

Key Takeaways:

• The study identified four SMTs (varespladib, marimastat, nafamostat, and dimercaprol) that demonstrated efficacy in preclinical models of snakebite envenoming.
• Varespladib, a secreted phospholipase A (sPLA) inhibitor, was granted orphan drug status for its potential to treat snakebite.
• The study found that varespladib potently inhibited snake venom phospholipase A (svPLA) activity in two snake species, with IC values of 0.221 and 0.276 mM, respectively.
• Marimastat exhibited potent inhibition of snake venom metalloproteinase (svMP) in several snake species, with IC values ranging from 0.0042 to 3.06 mM.
• Dimercaprol, a metal chelator, was a lower potency svMP inhibitor, with IC values ranging from 5.01 to 79.8 mM.
• Nafamostat proved to be an inhibitor of snake venom serine protease (svSP) in three snake species, with IC values ranging from 0.261 to 3.80 mM.
• The findings support the proposal that SMTs could be developed for therapeutic intervention in snakebite envenoming.

Statistics:

• Over 130,000 deaths and more than 400,000 disabilities occur annually due to snakebite envenoming worldwide.
• The study demonstrated the potential of SMTs to neutralize toxic components present in the venom of southern African snake species.
• The IC values for varespladib, marimastat, nafamostat, and dimercaprol ranged from 0.221 to 79.8 mM.
• The study found that these SMTs could be developed for therapeutic intervention in snakebite envenoming, with varespladib being granted orphan drug status for this purpose.

Sources:

• NewsRx. Investigators at North-West University Have Reported New Data on Chemicals and Chemistry (In vitro inhibition of snake venom toxins by varespladib, marimastat, nafamostat and dimercaprol). Chemicals & Chemistry. October 31, 2025; p 1289.
• In vitro inhibition of snake venom toxins by varespladib, marimastat, nafamostat and dimercaprol. Toxicon, 2025:108626.